Physical Optics Corporation (POC) proposes to develop a fiber optic dental probe that will enable dentists and oral surgeons to directly determine the type and condition of dental tissues in locations previously unviewable without ionizing radiation. The probe uses a unique high- strength metal-coated ultrafine optical fiber, coupled with a short- wavelength source, to excite the natural autofluorescence of teeth. A multi wavelength spectrograph collects the resulting fluorescent emission. Proprietary spectral analysis software is used to analyze the fluorescence, giving an unambiguous determination of tissue compounds and anatomical boundaries in real time. The probe's extremely small size will make it particularly useful in root canal surgery and in the diagnosis of periodontal disease. During Phase I, POC will use custom-fabricated optical fibers in the construction of the probe, which will be integrated with support hardware. The probe will be tested both mechanically and optically to verify its suitability for the proposed application. Simultaneous in vitro experiments on actual teeth will establish a base for the automated tissue health determination software. The two parallel efforts will be combined at the end of the project to present a working demonstration of the optical fiber dental microprobe concept. PROPOSED COMMERCIAL APPLICATION: The proposed micro-fiber dental sensor will find wide application in dentistry. Because of its small size, it can be used to locate the entrance of a root canal, follow curved canals, investigate subgingival regions for signs of periodontal disease or dental caries, and act as a valuable diagnostic adjunct in a host of other procedures including the curing of endodontic epoxies and the detection of hidden bacterial plaques. Potential spin-off applications include uses in microsurgery, remote fiber optic inspection, and qualification of mechanical parts.